Skiving machine



Dec. 30. 1924. v 1,521,110

- 1 H. W. KRAG SKIVING MACHINE Fiied June 29, 1923 7 I m/ iflii/gflfar:

Patented Dec. 30, 1924.

ITED STATES! HARRY w. KRAG, or sit. Louis, Misseniu, Assr'enon Toemissions? snot: MACHINERY AND 'To'oL COMPANY, or "sr. nears,ivirssouiai, A CORPORATION or Mfss'ounr sit-WING IVLLACH-INE.

Application filed-June 29, 1923. Serial No. 648,418.

To all whom it may concern.-

Be it known that l, HARRY WV. KRAG, a citizen of the United States, anda resident of the city of St. Louis and State of Missouri, have inventeda new and useful 11nproveinent in Skiving Machines, of which thefollowing is a specification.

My invention relates to skiving machines and has for its principalobject to devise a control mechanism for the knife of such machines thatwill keep a portion thereof in a fixed relation to the edge of upperroll of the skiving machine, regardless of the thickness of the materialoperated on thus making the cut material of uniform thickness at thatpoint. The invention consists principally in a compensating linkmechanism whereby the downward pull on the portion of the knife which itis desired to maintain in a predetermined position is off-set by anupward pressure. The invention further consists in the skiving machineand in the parts and combination of parts hereinafter described andclaimed.

In the accompanying drawing,

Fig. 1 is an elevation of a skiving machine embodying my invention;

Fig. 2 is a diagrammatical view of the knife control mechanism.

The skiving machine shown in the drawing comprises a frame 1 or standardin the upper end of which is rotatably secured a shaft 2 on the end ofwhich is a roll 3 that co-operates with a lower roll 4 that is rotatablymounted between the forked ends 5 of a rod 6 that is slidably mounted ina suitable bearing member 7 on the standard. A spring 8 is interposedbetween the rod 6 and a portion of the standard and tends to hold thelower roll 4 against the upper roll 3. A shaft 9 is rotatably mounted inthe standard and is provided with a handle 10 or other suitable meansfor turning it. A gear 11 on said shaft 9 meshes with a gear 12 on theshaft 2 that carries the upper roll 3.

One end of a knife table 13 is pivotally secured to a link 14 and thelink 14 is pivotally secured to one arm 5 of the forked member thatsupports the lower roll. A. knife 15 is secured to the knife table 13 bymeans of screws 16. The other end of the knife table 13 is pivotallysecured as by a pin 17 to a crank arm 18 that is pivotally secured tothe standard 1 as by a fulcrum pin 19. The other end of the crank 18pivotally secured to a-l ink 20 whose end is pivotally secured to aprojecting portion 21 of the fork member.

When leather or other material is fed into the machine, it forces thelower roll away from the upper roll. The fork member is thus lowered,and through the link the end of the knife table is lowered. The loweringof the forked member moves the link that is connected to the crank armand swings said crank arm, thus raising the portion of the crank armthat is connected with the knife table. Thus the end of the knife tableis raised. such that the portion of the knife with reference to the edgeof the upper roll (shown at A) remains constant, the lowering action ofone link being compensated for by the raising action of the other linkand crank arm. Thus the thickness of the material at the point (A) afterthe cut is always the same regardless of the thickness of the materialbeing operated on. The

action of the machine is diagrammatically shown in Fig. 2, and it willbe readily seen that the point (A) remains constant regardless of therelative position of the ends of the knife table.

Obviously numerous changes may be made without departing from theinvention and I do not wish to be limited to the precise constructionshown.

That I claim is:

1. A skiving machine comprising a frame, a pair of cooperating rolls, asupport for one of said rolls, said support being movable towards andaway from the other roller, a knife holder having a link connection withsaid support, a knife carried by said knife holder, and means secured tosaid knife holder and to the frame of the machine for maintaining aportion of said knife in fixed relation to said fixed rOll in allpositions of said movable roll and support.

2. A skiving machine comprising a frame, a roll rotatably mountedtherein, a forked support mounted in said frame so as to be movabletoward and away from said roll, a second roll rotatably mounted betweenthe forks of said support to cooperate with said first roll, a knifetable secured to said support, a knife secured to said table and meanfor maintaining a portion of said knife in The proportions of the partsare llH) llU

fixed relation to said first roll in all positions of said movable roll.

3. A skivmg machine comprising a frame,

a roll rotatably mounted therein, a forked support mounted in said frameso as to be movable toward and away from said roll, a second r011rotatably mounted between the forks of said support to cooperate Withsaid first roll, a knife table secured to said support, a knife securedto said table and means for maintaining a portion of said knife in fixedrelation to said first roll in all positions of said movable r011, saidmeans comprising a link pivotally secured to one fork of said supportand to the table, a crank pivotally mounted on theframe, one end of saidcrank being pivotally secured to said table and a second link pivotallysecured to the other fork of said support and to the end of the crank.

Signed at St. Louis, Missouri, this 26th day of June, 1923.

HARRY W. KRAG.

